Improvement in safety-valves



J. ARMSTRONG. SAFETY VALVE. No. 109,996. Patented Dec. 13, 1870.

acx m .iiii 9 1 a M I TM ml m w m m m m tan JASPER ARMSTRONG, OF"BROOKFIEL'D. MISSOURI.

Letters Patent No. 109,996, dated December 13, 1870.

IMPROVEMENT IN SAFETV-VALVES.

l'heBchodule referred to in the" Lott-n Patent and maldng put of thename.

To all whom it may concern Be it known that I, J ASPER Amts'rnoxe, ofBrook.- field, in the county of Linn and State of Missouri, haveinvented a new and useful Improvement -in Safety-Valve; and I do herebydeclare that the following is a. full, clear, and exact descriptionthereof,

which will enable others skilled in the art to make and use the same,reference being had to the accompanying drawingforining part of thisspecification.

This invention relates to'a new and useful improvement in satiety-valvesfor locomotives and other steamboilers, foe adding security to suchboilers by guard ing against an over-pressure of steam; and

It consists in the arrangement and construction of a. puppet-valve, withthe. parts connected therewith; as hereinafter more fully described.

In the accompanying drawing- Figure 1 represents a vertical longitudinalsection of the valve with its case and the parts connected therewith.

Figure 2 is a sectional top vienytakeu on the line x a: of fig. 1. 7

Similar letters of reference indicate corresponding parts. A. is thevalve, which works upon the stem B.

0' is n flange which surrounds the valve-seat.

E'is a spiral spring.

F is a collar on the lower end of the valve-stem, aspen which the springrests.

G. is a pocket or cylindrical casing which contains thespring, the upperend of which, H, is a portion of the valve-scat.

J represents the wings of the valre, \\"hich fit into the neck K of thecasing.

L is a shoulder at the lower endof the neck K, and M is a yoke on thetop of the spring which bears against the shoulder L and receives theupward pressui-c of the spring.

'The orifice for the valve-stein, through the valve, is tapering, 'so asto prevent binding.

The top portion of the valve-stem is provided with a screw-tln'ead.

N is a screw-nut on the valve-stem, the lower side ofwhich is globularin form and fits a globular cavity in the top of the valve, so that thenut and the valve form'a hall-and-socket joint. This allows the rod tooscillate without affecting the position of the valve on its seat.

The flange 0 surrounds a short cylinder, 0, the upper end of which formsa portion of the valve-seat, as seen at P in the drawing. "The flange Ois attached to the shell of the boiler, the casing and cylinder 0 beingwithin the boiler and subject to the pressure of the steam. I

- Between the neck K of the casing and the cylinder 0 there is anannular space, B, through which -the steam in the boiler has access tothe face of the valve.

S represents orifices through the top of the valve,

for the escape of steam when the pressure within theboiler raises thevalve.

It will be seen that the pressure of the steam is exerted on the valvein opposition to the force and strength of the spring, and that thespring is compressed to any required degree of tension by means of thenut N.

T T are flanged nuts on the screws U U,.the flanges of which lap overonto'the valve to limit the upward movement of the valve, and as asafeguard in case of accidents.

The advantages of this mode of attaching and operating the valve and thepinion for preventing the unseating of the'valve, by rneans of aball-ar1d-socket connection, are many, and must be obvious to all whoWitnesses W. D. HICKs,

D. A. Ronmsox.

